Hygienic requirements to natural light home

Normal natural lighting is important hygienic value. Light has a beneficial effect on the human body, activates metabolism, improves mood, increases efficiency.
Sufficient natural lighting of buildings depends on a number of reasons:
a) Windows orientation for the countries of the world. From a hygienic point of view, the most appropriate orientation to the South and South-East.
In middle latitudes of the long axis of the building must be directed from the North-East to South-West. However accommodations feature a South-East, and the subsidiary in the North-West.
Orient accommodations to the West is not recommended, as this orientation significant radiation in summer and low winter.
In Northern and southern latitudes of the USSR it is recommended that the axes of buildings from West to East (Equatorial) with the orientation of the Windows of the residential rooms on the South, and subsidiary to the North;
b) the size and location of Windows. The top edge of the window should be placed closer to the ceiling, which promotes deeper penetration of light into the room. The width of the walls should not exceed half the width of the window openings. Important for illumination have the numbers and size of the aperture, the nature of covers. The best form are rectangular Windows;
in) depth rooms (rooms with side-sided lighting is the distance from a wall with Windows to the opposite wall). The depth of the room should not exceed more than 2 times the distance from the top edge of the window to the floor (no more than 6.5 m);
g) the gap between buildings. This rent should be not less than twice the height of the opposite tall buildings;
d) the quality of the glass and purity. Ordinary glass absorb part of the world, particularly ultraviolet plot. Polluted glasses reduce light transmission by 25-50%. The curtains can absorb up to 40% of the light;
e) the nature of the painting of the walls and ceiling. Light tones in the reflected light, increase the illumination.
For characteristics of natural lighting use different indicators. One of them is the daylight factor (DF), meaning the ratio of light points inside the premises, illumination any point located on the same plane, located outside the room is illuminated by diffuse light of the sky. Its value is expressed as a percentage and is depending on the purpose of the premises and the nature of the work. For residential premises must be not less than 0.5%.
Light factor (SK) - the ratio glazed window surface to the area of the floor in the room. It is expressed as a simple fraction, where the numerator is the unit, the denominator is the number that shows what part of the floor area is glazed surface of Windows.
The normal length rate depends on the nature of the premises. For residential premises light factor shall not be less than 1/8-1/10.
Given bactericide and healing effect of the sunlight, it is advisable hospital room oriented to the South. Light factor in the chambers must be within 1:6-1:7, daylight factor - 1 %. Artificial lighting in the wards with incandescent lamps is 30 Lux, with luminescence - 75 LK. It is desirable for each bed had a local lighting. In the chambers shall be provided for night lighting.